The Linux Vehicle Recognition SDK is available in the commercial APT repository.
The libopenalpr-dev package will install the necessary headers and library packages into your system. To install, run:
bash <(curl -s https://deb.openalpr.com/install)
Select install_sdk from the menu.
You must be on Ubuntu version 18.04 or above.
Licensing
Before running the software you must obtain a license key. If you haven't already done so, please visit the Request a License section to submit your information.
After acquiring a license, paste the license key into the license.conf file to begin using the software. Alternatively, you can set the license as an environment variable named OPENALPR_LICENSE_KEY.
Command Line Utility
The Vehicle Recognition SDK includes a command line utility. Simply type alpr [image file path] to get started with recognizing license plate images.
For example, the following output is created by analyzing this image:
user@linux:~/openalpr$ alpr --help
USAGE:
alpr [-c <country_code>] [--config <config_file>] [-n <topN>] [--seek
<integer_ms>] [-p <pattern code>] [--clock] [-d] [-j] [--]
[--version] [-h] <image_file_path>
Where:
-c <country_code>, --country <country_code>
Country code to identify (either us for USA or eu for Europe).
Default=us
--config <config_file>
Path to the openalpr.conf file
-n <topN>, --topn <topN>
Max number of possible plate numbers to return. Default=10
--seek <integer_ms>
Seek to the specified millisecond in a video file. Default=0
-p <pattern code>, --pattern <pattern code>
Attempt to match the plate number against a plate pattern (e.g., md
for Maryland, ca for California)
--clock
Measure/print the total time to process image and all plates.
Default=off
-d, --detect_region
Attempt to detect the region of the plate image. [Experimental]
Default=off
-j, --json
Output recognition results in JSON format. Default=off
--, --ignore_rest
Ignores the rest of the labeled arguments following this flag.
--version
Displays version information and exits.
-h, --help
Displays usage information and exits.
<image_file_path>
Image containing license plates
